I've been stuck on this particular problem for about a week now, and I figure I'm going to write this up as a question on here to clear out my thoughts and get some guidance.
So I have this case class that has a java.sql.Timestamp field:
case class Request(id: Option[Int], requestDate: Timestamp)
and I want to convert this to a JsObject
val q = Query(Requests).list // This is Slick, a database access lib for Scala
printList(q)
Ok(Json.toJson(q)) // and this is where I run into trouble
"No Json deserializer found for type List[models.Request]. Try to implement an implicit Writes or Format for this type." Okay, that makes sense.
So following the Play documentation here, I attempt to write a Format...
implicit val requestFormat = Json.format[Request] // need Timestamp deserializer
implicit val timestampFormat = (
(__ \ "time").format[Long] // error 1
)(Timestamp.apply, unlift(Timestamp.unapply)) // error 2
Error 1
Description Resource Path Location Type overloaded method value format with alternatives:
(w: play.api.libs.json.Writes[Long])(implicit r: play.api.libs.json.Reads[Long])play.api.libs.json.OFormat[Long]
<and>
(r: play.api.libs.json.Reads[Long])(implicit w: play.api.libs.json.Writes[Long])play.api.libs.json.OFormat[Long]
<and>
(implicit f: play.api.libs.json.Format[Long])play.api.libs.json.OFormat[Long]
cannot be applied to (<error>, <error>)
Apparently importing like so (see the java scala playframework playframework-2.0